Marbled inks in motion. Blush, sage and lilac swirl slowly on cream, combed into soft ribbons the way ink lies on a marbling bath, and fine dark plum veins cut through them, swelling and thinning along their length. A sparser set of thin gold veins catches the eye.

A luxe, calm background for beauty, stationery, wedding, interiors and jewellery pages, product shots and titles. Set the paper, three inks, the vein and gold colours, how strongly the inks swirl, the scale, and the strength of each set of veins. The demo has three presets: Rose quartz, Ocean agate and Blush and gold.

What you get: a GLSL ES 3.00 fragment shader for plain WebGL2, an ES module that returns a three.js ShaderMaterial, a Shadertoy version, and a demo page that runs offline with a small settings panel. For video editors there is a 10-second 1920 x 1080 H.264 loop that plays end to start without a seam.

It runs in one pass with no textures needed, at about 3.1 ms of GPU time per frame at 1920 x 1080 on a recent laptop. The README covers set-up in WebGL2, three.js and Shadertoy, every uniform with its default and range, and performance notes.